137 research outputs found
The young, the old, and the government : demographics and fiscal multipliers
Este artículo muestra que el tamaño del multiplicador fiscal depende de la estructura demográfica de la población de una economía. Usando la variación en el gasto militar y las tasas de natalidad en los estados de los EE. UU., mostramos los multiplicadores fiscales locales aumentan con la proporción de jóvenes en la población total. Racionalizamos este hecho con un parsimonioso modelo neo-keynesiano de economía abierta, y con generaciones solapadas e imperfecciones del mercado crediticio. El modelo explica el 65 % de la relación entre los multiplicadores fiscales locales y la demografía. Usamos el modelo para estudiar las implicaciones del envejecimiento de la población y encontramos que en la actualidad los multiplicadores fiscales nacionales de los Estados Unidos son 36 % más bajos que en 1980We document that fiscal multipliers depend on the age structure of the population. Using the variation in military spending and birth rates across U.S. states, we show that local fiscal multipliers increase with the share of young people in total population. We rationalize this fact with a parsimonious life-cycle open-economy New Keynesian model with credit market imperfections. The model explains 65% of the relationship between local fiscal multipliers and demographics. We use the model to study the implications of population aging, and find that nowadays U.S. national fiscal multipliers are 36% lower than in 198
Inhibition of Y1 receptor signaling improves islet transplant outcome
Failure to secrete sufficient quantities of insulin is a pathological feature of type-1 and type-2 diabetes, and also reduces the success of islet cell transplantation. Here we demonstrate that Y1 receptor signaling inhibits insulin release in β-cells, and show that this can be pharmacologically exploited to boost insulin secretion. Transplanting islets with Y1 receptor deficiency accelerates the normalization of hyperglycemia in chemically induced diabetic recipient mice, which can also be achieved by short-term pharmacological blockade of Y1 receptors in transplanted mouse and human islets. Furthermore, treatment of non-obese diabetic mice with a Y1 receptor antagonist delays the onset of diabetes. Mechanistically, Y1 receptor signaling inhibits the production of cAMP in islets, which via CREB mediated pathways results in the down-regulation of several key enzymes in glycolysis and ATP production. Thus, manipulating Y1 receptor signaling in β-cells offers a unique therapeutic opportunity for correcting insulin deficiency as it occurs in the pathological state of type-1 diabetes as well as during islet transplantation.Islet transplantation is considered one of the potential treatments for T1DM but limited islet survival and their impaired function pose limitations to this approach. Here Loh et al. show that the Y1 receptor is expressed in β- cells and inhibition of its signalling, both genetic and pharmacological, improves mouse and human islet function.info:eu-repo/semantics/publishe
Electrical characterization of the junctions P+ N by C-V technique
Technique CV exploits measurement in mode of small signals for a relatively high frequency of the capacity of a junction metal-semi driver or a junction P+ NR (or PN+ polarized in reverse by a tension V R The experimental analysis of this technique makes it possible to determine some electric properties of the junctions P+ N or Schottky. We describe here, the method used and we expose then the results obtained by this technique on diodes containing silicon (Si).Technique CV exploits measurement in mode of small signals for a relatively high frequency of the capacity of a junction metal-semi driver or a junction P+ NR (or PN+ polarized in reverse by a tension V R The experimental analysis of this technique makes it possible to determine some electric properties of the junctions P+ N or Schottky. We describe here, the method used and we expose then the results obtained by this technique on diodes containing silicon (Si)
Labor Analgesia. A Systematic Review and Meta-Analysis of Non-Pharmacological Complementary and Alternative Approaches to Pain during First Stage of Labor
The aim of the study was to conduct a meta-analysis to evaluate the efficacy of non-invasive and nonpharmacological techniques on labor first-stage pain intensity. Literature databases were searched from inception to May 2021, and research was expanded through the screening of previous systematic reviews. Inclusion criteria were: (1) population: women in first stage of labor; (2) intervention: non-pharmacological, non-invasive, or minimally invasive intrapartum analgesic techniques alternative and/or complementary to pharmacological analgesia; (3) comparison: routine intrapartum care or placebos; (4) outcomes: subjective pain intensity; and (5) study design: randomized controlled trial. Risk of bias of included studies was investigated, data analysis was performed using R version 3.5.1. Effect size was calculated as difference between the control and experimental groups at posttreatment in terms of mean pain score. A total of 63 studies were included, for a total of 6146 patients (3468 in the experimental groups and 2678 in the control groups). Techniques included were massage (n = 11), birth balls (n = 5) mind-body interventions (n = 8), heat application (n = 12), music therapy (n = 9), dance therapy (n = 2), acupressure (n = 16), and transcutaneous electrical nerve stimulation (TENS) (n = 8). The present review found significant evidence in support of the use of complementary and alternative medicine for labor analgesia, and different methods showed different impact. However, more high-quality trials are needed
A simple quasi-3D theory for static stability analysis of imperfect FG beam
This study introduces a simplified approach to assess the buckling and static bending of advanced composite beams, including those composed of functionally graded materials (FGMs) with various porosity models. The technique utilizes a straightforward integral quasi-3D approach based on the advanced shear deformation theory. This approach offers several advantages: it simplifies the analysis by reducing the number of unknowns and equations required, improves accuracy by considering the stretch effect across the entire depth of the beam, resulting in more reliable results, and accurately represents shear by satisfying the zero-traction boundary conditions on the beam’s surfaces without the need for a shear correction factor. Additionally, it captures the parabolic pattern of transverse shear strain and stress throughout the depth of the beam. The governing equations are obtained by applying the concept of virtual work, and the Navier solution is employed to calculate analytical solutions for the buckling and static bending of FGM porous beams under different boundary conditions. The approach is in line with and builds upon existing research on FGMs and other sophisticated composite beams, further enhancing its validity and reliability. Finally, computational analyses demonstrate how the distribution of materials, such as power-law functionally graded materials (FGMs), geometry, and porosity, affect the deflections, stresses, and critical buckling load of the beam
The unusual mesophases and properties exhibited by a family of glycosteroids
In this article we describe research on the synthesis and characterization of a family of “Janus” amphiphiles composed of disaccharide head groups and alkaloid units joined together via a methylene linker, and bearing a lateral aliphatic chain of varying length. The condensed phases formed by self-organization of the products as a function of temperature were characterized by differential scanning calorimetry, thermal polarized light microscopy, and small angle X-ray scattering, allied with computational modelling and simulations. Structural studies on heating specimens from the solid showed that some homologues exhibited lamellar, columnar and bicontinuous mesophases, whereas the same homologues revealed different phase sequences on cooling from the amorphous liquid. We explore these unusual results, which are revealed via supercooling
Genome-wide association mapping revealed a diverse genetic basis of seed dormancy across subpopulations in rice (Oryza sativa L.)
Can the reproductive system of a rare and narrowly endemic plant species explain its high genetic diversity?
Relative intensities of the 3d-2p lines emitted by Ar¹³⁺ ions after impact excitation by an electron beam
The intensity ratio R of the dipole-allowed lines 3d²D_{3/2,5/2} → 2p²P_{3/2} and 3d²D_{3/2} → 2p²P_{1/2} emitted from highly charged boron-like Ar¹³⁺ ion collisionally excited by a monoenergetic electron beam has been theoretically studied versus electron densities from 10⁹ to 5× 10¹³ cm^{-3}. The calculations were performed at different angles θ of observation with respect to the electron beam direction and various incident-electron energies e_{ı} from 0.65 to 3 keV. By taking into account all important transitions among 290 magnetic sublevels of the 2s²2p, 2s2p², 2p³, 2s²3l, 2s2p3l, 2p²3l (l = 0-2) configurations, a collisional-radiative model has been used for determining the populations of the upper magnetic sublevels of the lines. All required atomic data were computed with the Flexible Atomic Code. We find that the effect of anisotropy in the photon emission, due to the directionality of the incident electron beam, can lead to very significant differences between R(0°) and R(90°). Our results also indicate that the contribution from the ²D_{3/2}→ ²P_{3/2} line which blends with the ²D_{5/2} → ²P_{3/2} line enhances the effect of anisotropy
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